1. Field of the Invention
The present invention relates to an endoscope system having a connector. More particularly, the present invention relates to an endoscope system in which an endoscope is connected by a connector with a related apparatus, and in which air-tightness or liquid-tightness can be ensured even in use of a plurality of connectors couplable selectively.
2. Description Related to the Prior Art
An endoscope is used widely in the medical field, and includes a fluid channel, such as a fluid supply channel for supplying air or water as fluid to a tip device of an elongated tube, and a suction channel for suction of fluid. An example of the endoscope has a balloon at the tip device of the elongated tube. A flow channel for inflating and deflating the balloon is provided in the endoscope. For those purposes, a fluid supply source is connected to the fluid supply channel, a suction apparatus is connected to the suction channel, and a balloon control apparatus is connected to the flow channel for supplying and drawing fluid. A port device or end sleeve is disposed at a proximal end of the fluid channel for connection of a related apparatus of those examples.
Connection of the fluid source apparatus or the related apparatus (suction apparatus) to the fluid channel of the endoscope requires a removable structure with respect to the port device of the fluid channel and also air-tightness or liquid-tightness. For example, JP-A 2006-149556 (corresponding to JP-B 4458258) and U.S. Pat. No. 5,971,917 (corresponding to JP-B 3712820) disclose seal packing positioned for sealing between the port device and a connector of the related apparatus, to press the seal packing to the port device.
JP-A 2006-149556 discloses a cleaning adapter or the connector for the endoscope. The connector includes a flow sleeve, the seal packing, a guide device of a housing, a slide mechanism and a coil spring. The flow sleeve is receivable in the port device of the endoscope. The seal packing seals the flow sleeve. The slide mechanism has the flow sleeve positioned stationarily, and is movable back and forth relative to the guide device. The coil spring is disposed between the slide mechanism and the guide device. The seal packing contacts an end face of the port device. Upon shifting the slide mechanism relative to the guide device, a flange of the port device is latched between the guide device and the flow sleeve. The coil spring presses the flow sleeve to tighten the contact of the seal packing with the port device. Also, U.S. Pat. No. 5,971,917 discloses the endoscope in which a male thread is formed with the port device. A female thread is formed with the connector, and helically engaged with the male thread to press the seal packing.
U.S. Pat. No. 7,568,735 (corresponding to JP-B 4144444), JP-A 9-201328 and JP-A 8-112247 discloses the endoscope and the connector in combination with the endoscope. A female tapered surface or tapered bore surface is defined inside the port device and has a predetermined taper angle. A male tapered surface or tapered sealing surface is formed at a tip of a coupling sleeve of the connector. The male tapered surface is tightly fitted on the female tapered surface by engaging the coupling sleeve with the inside of the port device, for maintaining air-tightness.
While the seal packing for sealing the port device of the endoscope is new, air-tightness and liquid-tightness are sufficient. However, degradation of the seal packing lowers tightness in the sealing with the port device, considerably to lose air-tightness and liquid-tightness. In view of this, a disposable type of the connector with the seal packing is useful for manipulation of entry of the elongated tube of the endoscope in a body cavity (gastrointestinal tract) for imaging, diagnosis and treatment of the body of the patient. The connector is connected to the related apparatus. In contrast with this, a reusable type of the connector is useful in combination with a syringe for cleaning, tube cleaning apparatus or the like for operation with durability with time. The reusable type does not include the seal packing but constructed for air-tightness and liquid-tightness.
Although the seal packing in the connector of JP-A 2006-149556 and U.S. Pat. No. 5,971,917 is effective in keeping air-tightness and liquid-tightness, mechanical construction is complicated, inclusive of the coil spring for pressing the flow sleeve, the slide mechanism for latching the flange of the port device, and the female thread for engagement with the port device. The connector cannot be disposable due to a considerably high manufacturing cost.
The construction of U.S. Pat. No. 7,568,735, JP-A 9-201328 and JP-A 8-112247 do not have the seal packing but have the female tapered surface and the male tapered surface fitted on each other to keep air-tightness and liquid-tightness in combination of the endoscope with the connector. However, there is no disclosure for precisely positioning the female tapered surface and the male tapered surface in the axial direction. Air-tightness or liquid-tightness may be insufficient assuming that the connector is used repeatedly with a tube cleaning apparatus or the like.